1. Technical Field
This invention relates to brewers, and more particularly, to commercial brewers for flavor containing solid materials.
2. Description of Related Art
It has been known for centuries to prepare coffee, tea, herb extracts and other flavor-containing liquids by steeping the corresponding flavor containing solid materials in hot water under ambient or elevated pressure. The steeping of roasted and ground coffee under ambient pressure emerged in the late 14th century and throughout the 19th and even the early 20th centuries, it was considered adequate to add ground coffee to hot water in a saucepan, boil the mixture until it smelled right, and pour the brew into a cup. It was not until later in the 20th century, that coffee making became somewhat automated.
The modern coffeemaker is a kitchen appliance used to brew coffee without having to boil water in a separate container. While there are many different types of coffeemakers using a number of different brewing principles, in the most common devices, coffee grounds are placed in a paper or metal filter inside a funnel. The funnel is then set over a glass or ceramic coffee pot. Cold water is poured into a separate chamber, and the water is heated up to the boiling point and directed into the funnel. This is commonly called an automatic drip-brew or drip brew coffee maker and is the most popular method used to brew coffee or tea.
Extraction time, water volume and water temperature are among the most critical considerations when brewing coffee with a drip brew coffee maker and in order to achieve a consistent tasting coffee, all three must be kept relatively constant. Typical hot water tank type brewers maintain the temperature of the water in the tank at a preset level through the use of a thermostat.
When a brewing cycle is selected in a typical tank type brewer, water solenoids are opened or closed by an electronic or electromechanical timer. The solenoids control the flow of water from a tank to a basket that contains the solid flavor material to be brewed. To replace the hot water sent to the brewing basket from the tank, cold water from a water source flows into the tank as the hot water is sent to the basket. This water inflow causes the tank temperature to drop during the brew cycle, effecting the extraction of the product from the flavor containing solid material. Various control systems, including solid-state controls, have been used to improve the operation of tank brewers and improve extraction of product. However, the effectiveness of these control systems is arguable, as they have a problem with consistent control, are typically not efficient, and do not keep the temperature and volume of water used relatively constant from brew cycle to brew cycle.
What is needed is a brewer that can heat the water quickly and uniformly and then deliver the water to the material to be brewed in a manner that will enhance the brewing. In addition, the brewer should not use a time based method to measure the amount of water used. It would be beneficial if a more accurate system was used determine the water volume for each brewing cycle.